@Brendan227 From the hosting perspective, the first thing you need to be aware of is that remote hosting (when you live a long distance away from your bnb) can be difficult. You will need a local co-host, someone you can trust who can be available on short notice to physically attend the property if needed and manage any guest requirements, e.g. repairs, problems, enquiries about local services etc.
You will also need a reliable cleaner who can clean to hospitality industry standards. Best to look for a cleaner with experience in this area as a standard house clean won't cut it, it needs to be perfect and done exactly as requested to Enhanced Cleaning Protocol standards every time without fail. Last minute in-person inspection prior to guest arrival matters. Best not to have your cleaner as your co-host for this reason - you need a separate pair of eyes checking the place over.
I'm not sure about the PT PMA requirements but suggest you speak with someone in Bali about this. There seems to be plenty of advice on this available on the internet.
The business climate for tourism in Bali is not wonderful at present and that may not change for some time until international travel resumes to something more pre-covid levels. Alan Joyce CEO of Qantas reckons it will be 2024 before international travel returns to normal, so whatever revenue you think you will obtain needs to factor in a very slow recovery and reduced business. There are likely to be many villas on the market over there at present (lots of hosts have gone to the wall), so perhaps you should look at buying an established place instead. I have no idea how difficult it would be to build there at present but there might be issues with supply of materials, particularly anything imported.
Btw, when you post here, if you type the @ symbol, it will bring up the list of people you might want to respond to, just select that person and it will auto-populate in your reply. When you @Brendan227 or @Sharon1014 for example, the system will auto-advise via email that you have a response awaiting, otherwise ppl don't know that you have posted something unless they actually check the thread you started.
Hope this helps. Cheers.